GeminiFocus October 2016 | Page 17

GHOST predicted performance (dashed red line) against other current instruments in the field today. Andy also described the unique scientific role GHOST will have in an international context, from exoplanets to the distant Universe. GHOST Progressing Through Build Phase The Gemini High-resolution Optical SpecTrograph (GHOST) project continues to progress through the build phase. When completed, this instrument will bring long-desired capabilities at a high level of performance to Gemini South. At the June 2016 conference of the international society for optics and photonics (SPIE), held in Edinburgh, Scotland, several GHOST project team members reported on the project’s status. Andy Sheinis, Head of Instrumentation at the Australian Astronomical Observatory (AAO), which leads the multi-institution team building GHOST, described the technical advances incorporated into the instrument. GHOST is designed to deliver R = 50,000 and R= 75,000 spectroscopy for up to two objects simultaneously. GHOST uses a fiber-based image slicer to allow for a much smaller spectrograph than that described by the resolution-slit–width product; it will also have a sensitivity in the wavelength range between 363-950 nanometers (nm) that equals or exceeds that of similar instruments on other world-class facilities. Figure 1 shows the chart that Andy presented at the SPIE conference, which compares the October 2016 Figure 1. GHOST expected performance comparison against other current instruments in the field today. Also presenting at SPIE from the GHOST project team were Software Project Manager Peter Young, Software Engineer Jon Nielson, and Project Scientist Mike Ireland — all from the Australian National University. Peter and Jon presented a paper and poster on how GHOST will be controlled with software using the Gemini Instrument Application Programmer Interface (GIAPI), the newest Gemini software framework. Mike’s paper and poster showed the precision radial velocity error budget for the instrument, obtained from end-to-end simulations. Although GHOST was not designed for radial velocity precision, the 10 meters per second requirement is feasible; GHOST may also achieve a significantly higher performance than this. John Pazder, Project/Optical Engineer at the National Research Council Canada Herzberg (NRC-H), presented a paper and poster covering the optical design of the benchmounted spectrograph and the predicted resolution and efficiency for the spectrograph. The following GHOST project team members were also in attendance: Project Manager/Detector Engineer Greg Burley, from NRC-H; Optics Engineer Ross Zhelem, from AAO; and Instrument Scientist Steve Margheim, Systems Engineer Andrew Serio, and Project Manager David Henderson, from Gemini. The NRC-H team building the bench-mounted spectrograph subsystem recently re- GeminiFocus 15